Rivaroxaban for the treatment of noncirrhotic splanchnic vein thrombosis: an interventional prospective cohort study.

Heparins and vitamin K antagonists are the mainstay of treatment of splanchnic vein thrombosis (SVT). Rivaroxaban is a potential alternative, but data to support its use are limited. We aimed to evaluate the safety and efficacy of rivaroxaban for the treatment of acute SVT. In an international, single-arm clinical trial, adult patients with a first episode of noncirrhotic, symptomatic, objectively diagnosed SVT received rivaroxaban 15 mg twice daily for 3 weeks, followed by 20 mg daily for an intended duration of 3 months. Patients with Budd-Chiari syndrome and those receiving full-dose anticoagulation for >7 days prior to enrollment were excluded. Primary outcome was major bleeding; secondary outcomes included death, recurrent SVT, and complete vein recanalization within 3 months. Patients were followed for a total of 6 months. A total of 103 patients were enrolled; 100 were eligible for the analysis. Mean age was 54.4 years; 64% were men. SVT risk factors included abdominal inflammation/infection (28%), solid cancer (9%), myeloproliferative neoplasms (9%), and hormonal therapy (9%); 43% of cases were unprovoked. JAK2 V617F mutation was detected in 26% of 50 tested patients. At 3 months, 2 patients (2.1%; 95% confidence interval, 0.6-7.2) had major bleeding events (both gastrointestinal). One (1.0%) patient died due to a non-SVT-related cause, 2 had recurrent SVT (2.1%). Complete recanalization was documented in 47.3% of patients. One additional major bleeding event and 1 recurrent SVT occurred at 6 months. Rivaroxaban appears as a potential alternative to standard anticoagulation for the treatment of SVT in non-cirrhotic patients. This trial was registered at www.clinicaltrials.gov as #NCT02627053 and at eudract.ema.europa.eu as #2014-005162-29-36.

Direct oral anticoagulants for extended treatment of venous thromboembolism: insights from the EINSTEIN CHOICE study.

The risk of recurrence of venous thromboembolism (VTE) persists after interruption of the initial anticoagulation therapy. New evidence shows that direct oral anticoagulants are effective for extended treatment of VTE and may reduce the risk of all-cause mortality. The optimal duration of anticoagulation after VTE is, however, controversial and complicated by the need for individualised assessment and balance between thrombosis and bleeding risks. Three direct oral anticoagulants (rivaroxaban, apixaban and dabigatran) have been studied for extended treatment of VTE. Dabigatran was shown to be safer than vitamin K antagonists and similarly effective for the prevention of recurrent VTE. Dabigatran, apixaban and rivaroxaban resulted in significant decreases in the rate of recurrent symptomatic VTE when compared to placebo, without a statistically significant difference in the risk of major bleeding. The latest guidelines of the American College of Chest Physicians suggest the use of low-dose aspirin to prevent VTE recurrence in patients who want to stop anticoagulation. In the randomised, double-blind, phase 3 EINSTEIN CHOICE trial, once-daily rivaroxaban at doses of 20 mg or 10 mg and 100 mg of aspirin were compared in VTE patients for whom there was clinical equipoise for extended anticoagulation. Either a treatment dose (20 mg) or a prophylactic dose (10 mg) of rivaroxaban significantly reduced the risk of VTE recurrence without a significant increase in bleeding risk compared with aspirin. The EINSTEIN CHOICE trial included patients with provoked or unprovoked VTE. Patients with VTE provoked by minor persistent or minor transient risk factors enrolled in this trial had not-negligible VTE recurrence rates. These new findings on extended therapy suggest the possibility of anticoagulation regimens at intensities tailored to the patients' risk profiles and VTE characteristics, with a shift of the risk-benefit balance in favour of extended treatment.

Safety ad efficacy of direct oral anticoagulants for extended treatment of venous thromboembolism.

Currently available anticoagulants have limitations for long-term treatment of venous thromboembolism (VTE). We have evaluated the efficacy and safety of direct oral anticoagulants (DOACs) for extended treatment of VTE. Four randomized controlled trials (RCTs) comparing DOACs (apixaban, rivaroxaban, and dabigatran) with placebo or warfarin for extended treatment of VTE were published. Primary efficacy outcome was recurrent VTE or VTE-related death, and primary safety outcome was major bleeding. DOACs significantly lower the risk of recurrent VTE or VTE-related death compared to placebo/warfarin, as well as all-cause mortality. Risk of major bleeding is not different with DOACs compared to placebo/warfarin. However, DOACs are associated with a significantly higher rate of the composite of major and clinically relevant bleeding compared to placebo. In conclusion, DOACs are effective and safe for the extended treatment of VTE, and may reduce the risk of all-cause mortality.

Effect of Vitamin K Intake on the Stability of Treatment with Vitamin K Antagonists: A Systematic Review of the Literature.

Vitamin K antagonists (VKA) are highly effective for the primary and secondary prevention of arterial and venous thromboembolic events. However, patients treated with VKA have on average only 60% of their international normalized ratio (INR) values within the therapeutic range and INR instability is associated with an increased risk of thrombosis and bleeding events. Recent evidence suggests that poor dietary vitamin K intake may affect anticoagulation control, but the role of vitamin K in INR stability remains to be established. We performed a systematic review of the literature to assess the role of vitamin K dietary intake on the stability of VKA and the potential effect of daily vitamin K supplementation on VKA therapy. After a search in Medline and EMBASE databases, 15 studies for a total of 1,838 patients were included in our systematic review. Observational studies suggest an increased risk of unstable anticoagulation control in patients with lower daily vitamin K intake. On the other hand, the role of daily vitamin K supplementation or a diet with controlled vitamin K content in patients on VKA treatment remains to be established. Use of daily vitamin K supplementation may be associated with a clinically relevant increase in the time in therapeutic range in patients with unstable anticoagulation control. Conversely, this effect appears small and not clinically relevant when vitamin K was administered to an unselected population receiving VKA. Other large prospective studies are necessary to confirm our preliminary findings.